JP2013218167A - Cleaning device, process cartridge, and method of mounting cleaning member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning member in which increase in a driving torque at the time of driving an image carrier and turn-up of a blade portion are suppressed, and position accuracy of the blade portion is improved.SOLUTION: A cleaning member 11 comprises: a blade portion 11c that abuts a cleaned body 1 in a counter direction to a moving direction R1 of the cleaned body 1; and a supporting part 11a that supports the blade portion 11c, has flexibility, and includes one end portion 11a1 provided with the blade portion 11c, the other end portion 11a2, an abutting portion 11c1 which is located between the one end portion and the other end portion and adapted to abut the cleaned body, and a bent part 11a3 that is located on a side being separated outward from the surface of the cleaned body with respect to a line segment L1 connecting the abutting portion 11c1 to a fixed portion 11a4 fixed to a frame body 14 provided on the other portion. The fixed portion 11a4 of the cleaning member 11 is fixed via injection-molded resin 17 to the frame body 14.

Description

  The present invention relates to a cleaning device, a process cartridge, and a method for attaching a cleaning member.

  Here, the cleaning device refers to a device for removing the developer from the object to be cleaned. The process cartridge refers to a cartridge in which at least the image carrier and the cleaning device are integrated into a cartridge and can be attached to and detached from the image forming apparatus.

  In an image forming apparatus, a cleaning blade system is used as a cleaning means for removing a developer remaining on an image carrier after a developer image formed on the image carrier is transferred to a recording medium in order to repeatedly use the image carrier. It has been known.

  The cleaning blade method is a method of removing the developer from the surface of the image carrier by bringing an elastic blade into contact with the surface of the image carrier with a predetermined pressure.

  In Patent Document 1, the cleaning member has a structure in which a blade is attached to the tip of a sheet metal as a support portion by molding. Then, the cleaning member is fixed by attaching the sheet metal to the frame body with screws or the like, thereby being brought into contact with the surface of the image carrier at a predetermined pressure.

JP 2002-341721 A

  However, with the widespread use of image forming apparatuses such as printers, there is a tendency for miniaturization, high speed, and high image quality. If the image forming apparatus is downsized, the size of the image carrier is reduced. In addition, the image carrier rotates faster due to the higher speed. That is, the blade that is in contact with the surface of the image carrier causes the image carrier to slide repeatedly on the surface of the image carrier at a high speed. Then, the temperature of the blade itself rises and the hardness of the blade becomes soft. As a result, the frictional force between the image carrier surface and the blade increases. As a result, there may be problems such as an increase in driving torque for driving the image bearing member and blade curl. Furthermore, recently, a developer having a spherical shape may be used to improve image quality. In this case, in order to remove the developer from the surface of the image carrier, it is necessary to increase the contact pressure of the blade against the image carrier, which is one of the factors that promote the above-described problem.

  Therefore, the present invention has been made to solve the above-described problems of the prior art. An object of the present invention is to provide a cleaning device capable of suppressing an increase in driving torque when driving an image carrier and curling of a blade, and a method for attaching a cleaning member. It is another object of the present invention to provide a cleaning device that improves the positional accuracy of the blade portion and a method for attaching the cleaning member.

  A typical configuration of the present invention for solving the above-described problems is a frame, a cleaning target, and a cleaning member that removes the developer from the cleaning target in a cleaning device used in an image forming apparatus. A blade part that contacts the object to be cleaned in a counter direction with respect to the moving direction of the image carrier, and a support part that supports the blade part and has flexibility, and the blade part is provided. One end portion, the other end portion, the abutting portion that is located between the one end portion and the other end portion, and the blade portion abuts on the object to be cleaned, and the other end portion A cleaning member having a support portion having a bent portion positioned on a side away from the surface of the object to be cleaned with respect to a line segment connecting the fixed parts fixed to the frame. And the cleaning member is Wherein the fixed portion is fixed through the injection-molded resin.

  According to the present invention, it is possible to stabilize the contact pressure of the cleaning member to the image carrier, and to suppress an increase in driving torque when the image carrier is driven and to curl the blade portion. Moreover, when the cleaning member is attached to the frame, the positional accuracy of the blade portion can be improved.

Cleaning device in embodiment Image forming apparatus in embodiments Description of rubber shape of cleaning member in embodiment Explanation of intrusion amount δ Explanation of positioning hole of cleaning member in embodiment Deflection of the cleaning member position in the embodiment Deflection of the cleaning member position when fixed with screws Explanation of cleaning device of comparative example

  Hereinafter, an example of an image forming apparatus according to the present invention will be described. The image forming apparatus 100 shown in FIG. 2 is an electrophotographic image forming apparatus, and FIG. 2 is a longitudinal sectional view showing a schematic configuration thereof.

  A photosensitive drum 1 serving as an image carrier (charged body) is disposed at substantially the center of an image forming apparatus main body (hereinafter simply referred to as “apparatus main body”) M. The photosensitive drum 1 has an OPC (organic optical semiconductor) photosensitive layer formed on the outer peripheral surface of a conductive drum base such as aluminum, and has a predetermined process speed (circumferential speed) in the direction of an arrow R1 about the axis q. It is rotationally driven at 200 mm / s.

  The surface (circumferential surface) of the above-described photosensitive drum 1 is uniformly (uniformly) charged to a predetermined polarity and potential by a charging roller 5 as a charging unit described later. The surface of the photosensitive drum 1 after charging is subjected to scanning exposure of a laser beam output from a scanner 6 as an exposure means and modulated in accordance with a time-series electric digital pixel signal of target image information. In response, an electrostatic latent image corresponding to the target image information is formed. The formed latent image is developed as a toner image with the toner 8 in the developer attached thereto by a developing device 7 as a developing means.

  On the other hand, the recording material 9 is fed by the paper feed roller 20 and sent to the transfer nip portion between the photosensitive drum 1 and the transfer roller 10 so as to be synchronized with the toner image formed on the surface of the photosensitive drum 1. A toner image is transferred to the surface. A transfer transfer bias is applied to the transfer roller 10 from a transfer bias application power source during transfer.

  The recording material 9 onto which the toner image has been transferred is separated from the surface of the photosensitive drum 1 and conveyed to a fixing device 4 as fixing means, where it is heated and pressurized to fix the toner image on the surface. On the other hand, after the toner image is transferred, the toner remaining on the surface without being transferred to the recording material 9 is removed by a cleaning member 4 as a cleaning unit, and used for the next image formation.

  The apparatus main body M is configured such that the process cartridge 12 is detachable. In the process cartridge 12, four process devices including a photosensitive drum 1, a charging roller 5, a developing device 6, and a cleaning member 11 are integrally incorporated in a cartridge container.

  As shown in FIG. 1, the cleaning device 15 has a configuration in which a cleaning container 11 and a squeeze sheet 13 are provided in a cleaning container 14. The cleaning member 11 is in contact with the surface of the photosensitive drum 1 and scrapes off the remaining toner. The squeeze sheet 13 is positioned below the cleaning unit 11 and contacts the surface of the photosensitive drum 1 in order to scoop off the toner scraped off from the surface of the photosensitive drum 1. Next, the cleaning device of Example 1 will be described.

[Example 1]
FIG. 1 shows the overall configuration of the cleaning device 15 and the cleaning member 11 in this embodiment. In FIG. 1, the charging roller 5 is omitted. The cleaning member 11 includes a support portion 11a made of a flexible metal thin plate and a blade portion 11c that is integrally formed with one end portion 11a1 of the support portion 11a and contacts the moving direction R1 of the photosensitive drum 1 in the counter direction. Have And between the one end part 11a1 and the other end part 11a2 of the support part 11a, it has the bending part 11a3. Further, the fixed portion 11a4 provided in the other end portion 11a2 is fixed via a resin 17 that is injection-molded in a concave portion 16 that is a fixing portion provided in the cleaning container 14 that is a frame body. Thereby, the cleaning member 11 is fixed to the cleaning container 14. Details will be described later. The bent portion 11a3 is located at a position away from the surface of the photosensitive drum 1 with respect to a line segment L1 that connects the abutting portion 11c1 where the blade portion 11c abuts on the photosensitive drum 1 and the fixed portion 11a2. is there. Further, the fixed portion 11a2 is located downstream of the contact portion 11c1 in the movement direction R1 of the photosensitive drum 1.

  As the material of the support portion 11a, SUS having a thickness of 0.2 mm was used. The plate-like springy member was uniformly bent at about 90 ° in the direction of the rotation axis q of the photosensitive drum 1. At this time, the distance from the fixed portion 11a2 to the bent portion 11a3 was 12 mm, and the distance from the bent portion 11a3 to the tip of the blade portion 11c was 12 mm.

  In this embodiment, as the plate-like spring member, for example, a phosphor bronze plate or other member having spring characteristics can be used. In addition, a vibration damping member having elasticity can be used instead of these metal plate-like springy members.

  The blade part 11c is urethane rubber having a JISA hardness of 70 degrees. FIG. 3 is an enlarged view of the blade portion 11c. The shape of the blade portion 11c is k = 3.0 mm, l = 2.0 mm, m = 1.0 mm, and n = 1 in order to reduce the deformation effect of the tip. Evaluation was performed at about 0.0 mm. As a method of bonding the support portion 11a and the blade portion 11c, a method using a double-sided tape or a hot melt adhesive is used in addition to the integral molding.

  Next, a method for attaching the cleaning member 11 to the cleaning container 14 which is a feature of the present embodiment will be described.

  The essence of the mounting method of the present embodiment is that the fixed position 11a4 is determined in a state where neither the blade part 11c nor the support part 11a is stressed (deformed) after the tip position of the blade part 11c is determined by a jig or the like. Is to be fixed to the recess 16. In the cleaning device in which the cleaning blade is fixed by such a method, the cleaning member 11 can be assembled at a desired predetermined position without the tip position of the blade portion 11c being displaced after the assembly.

  The cleaning container 14 is formed of high impact polystyrene resin (HI-PS), and the same material is used for the resin 17 injection molded in the recess 16. This resin is a thermoplastic resin, which is melted by applying heat and cured by cooling to room temperature.

  As shown in FIG. 1, the size of the space of the concave portion 16 in the cleaning container 14 is such that the fixed portion 11 a 4 can be accommodated in the space of the concave portion 16 even when the tolerance of the support portion 11 a and the bent portion 11 a 3 is taken into consideration. Size is secured. The fixed portion 11a4 is inserted into the space of the concave portion 16 without being in contact therewith, and the tip of the blade portion 11c is positioned at a position where the penetration amount δ with respect to the photosensitive drum 1 becomes 1.0 mm. As shown in FIG. 4, the intrusion amount δ is an amount in the direction perpendicular to the support portion 11a where the tip of the blade portion 11c before the photosensitive drum 1 is assembled into the virtual drum 1a has entered. The virtual drum 1a represents the position of the photosensitive drum 1 that would be present when the cleaning container 14 is assembled with the photosensitive drum 1 by a dotted line.

  As for the positioning of the tip of the blade part 11c, as shown in FIG. 5, the positional accuracy on a fixing jig (not shown) is obtained by using a round hole 11a1a and a long hole 11a1b provided in one end part 11a1 of the support part 11a. It is made to fit in the boss provided on the plane. Furthermore, the tip position (set angle, amount of penetration) of the blade portion 11c is determined by bringing the one end portion 11a1 and the plane of the fixing jig into close contact with each other.

  Thereafter, the support portion 11a and the cleaning container 14 are fixed by injecting the resin 17 in a molten state by applying heat to the space of the concave portion 16 and curing the resin 17 by cooling at room temperature. By fixing the cleaning member 11 to the cleaning container 14 by such a method, the tip position of the blade portion 11c can be accurately positioned regardless of the accuracy of the bending angle of the bending portion 11a3.

  6 shows the case where the cleaning member 11 is fixed by the fixing method of the present embodiment, and FIG. 7 shows the case where the angle of the bent portion is swung when the cleaning member 111 is fixed by the screw 103 as a comparative example. The state of a fixed part is shown. A solid line indicates a case where the angle of the bent portion is a center value, and a dotted line indicates a case where the angle of the bent portion is touched with a tolerance. In the embodiment of FIG. 6, since the tip position of the blade portion 11c is positioned, the position of the blade portion 11c is constant and the position of the fixed portion 11a4 varies. On the other hand, in the comparative example of FIG. 7, since the fixed portion 111a4 is fixed to the fixing portion 117 with the screw 103, the position of the fixed portion 111a4 is constant, but the position of the blade portion 111c is touched.

  The effect of the present embodiment will be confirmed below.

  Assuming the upper and lower limits of the bending angle when the angle of the bending portion 11a3 is 90 ° as the cleaning member 11 of the present embodiment and the bending tolerance is ± 1 °, the data of 91 ° and 89 ° are obtained. Table 1 shows. Further, as a comparative example, data in which the fixed portion 111a4 as shown in FIG. 8 is fixed to the cleaning container 114 with the screw 103 and the bending portion 11a3 has an angle of 90 °, 91 °, and 89 ° are also shown in Table 1. . Specifically, the intrusion amount δ and the pressure per unit length received by the drum when the drum was attached were measured. The results are shown in Table 1.

  As shown in FIG. 1, in this embodiment, the penetration amount is constant regardless of the bending angle, and in the comparative example, the penetration amount δ is displaced by about 210 μm depending on the bending angle. In this embodiment, the fluctuation of the pressure per unit length received by the photosensitive drum 1 when the photosensitive drum 1 is assembled is about ± 2 gf / cm at the upper and lower limits of the bending angle. It can be seen that the comparative example is as large as ± 16 gf / cm. In the comparative example, the pressure fluctuation also increases because the intrusion amount of the cleaning blade changes greatly. In this embodiment, the intrusion amount δ does not vary, but the pressure varies by about ± 2 because the position of the fixed portion 11a4 varies depending on the bending angle of the bending portion 11a3. .

  From this result, it can be seen that the cleaning device to which the cleaning member is attached by the method of the present embodiment can be assembled with a stable pressure even if the bending angle varies to some extent as compared with the comparative example.

  Moreover, in the present Example, positioning in the one end part 11a1 was performed using the fixing jig. However, the positioning boss is provided in a portion of the cleaning container 14 corresponding to the position of the round hole and the long hole of the one end 11a1, and the boss is separated from the round hole and the long hole when the photosensitive drum 1 is assembled. The same effect can be obtained.

  In the present embodiment, the recess 16 is provided in the cleaning container 14. However, the fixed portion 11 a 4 of the cleaning 11 is limited to the recess 16 as long as it can be fixed to the cleaning container 14 through the molten resin 17. It is not a thing.

  Further, in this embodiment, the fixed portion 11a2 is inserted into the cleaning container 14 in the space of the concave portion 16 so as not to contact. However, if the contact pressure of the blade portion 11c to the photosensitive drum 1 does not vary extremely, the fixed portion 11a2 may be in contact with the concave portion 16 and fixed with the resin 17.

  In this example, high impact polystyrene resin (HI-PS) was used as the molten resin. However, it may be an acrylonitrile / butadiene / styrene copolymer (ABS) resin, a modified poly (phenylene) ether resin (mPPE), a modified poly (phenylene) oxide (PPO), or the like.

  In this embodiment, a thermoplastic resin is used. However, even if a thermosetting resin is poured into the joint portion of the housing in a molten state and cured by applying heat, the same effect can be obtained.

  As described above, in this embodiment, the cleaning member that removes the toner from the photosensitive drum as the member to be cleaned has been described. However, the member to be cleaned may be a transfer belt as a transfer member to which a toner image that is a developed image is transferred from the photosensitive drum.

  As described above, it is possible to stabilize the contact pressure of the cleaning member to the image carrier, and to suppress an increase in driving torque when the image carrier is driven, and to curl the blade portion. Moreover, when the cleaning member is attached to the frame, the positional accuracy of the blade portion can be improved.

DESCRIPTION OF SYMBOLS 1 Photosensitive drum 11 Cleaning member 11a Support part 11a1 One end part 11a2 Other end part 11a3 Bending part 11a4 To-be-fixed part 14 Frame 17 Resin

Claims (11)

In a cleaning device used in an image forming apparatus,
A frame,
A body to be cleaned;
A cleaning member that removes the developer from the object to be cleaned, a blade part that contacts the object to be cleaned in a counter direction with respect to a moving direction of the object to be cleaned, and a flexible member that supports the blade part and is flexible A support portion having one end portion provided with the blade portion, the other end portion, and between the one end portion and the other end portion, and the blade portion abuts on the object to be cleaned. A bending portion located on the side away from the surface of the object to be cleaned, with respect to a line segment connecting the contact part and the fixed part fixed to the frame provided at the other end; and A support member having a cleaning member,
Have
The cleaning device, wherein the fixed portion is fixed to the frame body via a resin in which the fixed portion is injection-molded.   The cleaning device according to claim 1, wherein the fixed portion is fixed through the resin without contacting the frame.   The cleaning device according to claim 1, wherein the fixed portion enters a recess provided in the frame body and is fixed by the resin injection-molded in the recess.   The said support part has a positioning part by which the said cleaning member is positioned when the said to-be-fixed part is fixed to the said frame, The one of Claim 1 thru | or 3 characterized by the above-mentioned. Cleaning device.   The cleaning apparatus according to claim 1, wherein the member to be cleaned is a photosensitive drum on which an electrostatic latent image is formed.   The cleaning apparatus according to claim 1, wherein the member to be cleaned is a transfer member to which a developed image is transferred. A process cartridge that can be attached to and detached from the main body of the image forming apparatus,
A cleaning device according to claim 5;
The photosensitive drum;
A process cartridge. A cleaning member that removes the developer from the object to be cleaned, the blade part contacting the object to be cleaned in a counter direction with respect to the moving direction of the object to be cleaned, and supporting the blade part to provide flexibility. A support portion that is located between one end portion provided with the blade portion, the other end portion, and the one end portion and the other end portion, and the blade portion is in contact with the object to be cleaned. A bending portion located on the side away from the surface of the object to be cleaned with respect to a line segment connecting the fixed part fixed to the frame body provided at the other end part. A cleaning member having a support, and a method of attaching the frame to the frame,
Positioning the cleaning member at a predetermined position with respect to the frame,
A method for attaching a cleaning member, wherein a resin is injection-molded on the frame, and the fixed portion is fixed to the frame via the resin.   9. The attachment method according to claim 8, wherein the cleaning member is positioned without the fixed portion being in contact with the frame body and fixed through the resin.   The attachment method according to claim 8 or 9, wherein the cleaning member is positioned by allowing the fixed portion to enter a recess provided in the frame.   The attachment method according to claim 8, wherein the cleaning member is positioned by a positioning portion provided in the support portion.

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